Editor’s Note (August 2016): Maps, rich media, and text have been updated to reflect a taxonomic change/split for this species. This species account is still being edited and may contain content from an earlier version of the account.
The Western Grebe is a conspicuous water bird of western North America, from southern Canada to the Mexican Plateau. They are perhaps best known for their elaborate and energetic courtship rituals, now well-studied. These courtship ceremonies -- in which these birds perform a series of displays in ritualized, apparently mechanical, sequences -- are among the most complex known in birds.
Western Grebes and their former conspecifics, Clark's Grebe, are unique among grebes in possessing a mechanism in the neck that permits them to thrust forward the head like a spear. Such a mechanism is well known in herons and anhingas, but its details remain to be worked out in these grebes.
Because the Western and Clark's grebes were considered color phases of one species—the Western Grebe—from 1886 until 1985, the literature on them was combined under that name. Only rarely was mention made of the “phase” of the birds studied. Because of this, and because of the great similarity between the two species in morphology and behavior, this account contains references that may pertain to both species. First, under Western Grebe, is given the information known to apply to that species alone, followed by information common to both species, and that for which the “phase” was not mentioned. The Clark's Grebe account consists of information known to apply to that species and to known differences between the two.
Although the behavior of the northern subspecies of these birds has been well studied, little is known of their longevity and movements, owing to a paucity of banding recoveries. Parallel studies on the biology of the Mexican races of these species could greatly aid our understanding of the evolution of these species.